Mine Water Issues addressed in the project train@mine · year of the project revealed a number of issues that were addressed in training courses designed on a pilot scale. Four two-day

Mine Water Issues addressed in the project train@mine

Florian Werner1, Johannes Meßer

1, Uwe Seeger

2, Michael Struzina

3

1Emscher Wassertechnik, Brunnenstr. 37, 45128Essen, Germany, [email protected] 2RAG MS, RAG Mining Solutions GmbH, Shamrockring 1, 44623 Herne, Germany, bernd-

[email protected] 3Mitteldeutsche Braunkohlengesellschaft mbH, Glück-Auf-Straße 1, 06711 Zeitz, Germany,

[email protected]

Abstract

In the joint project train@mine two German mining companies (RAG and MIBRAG), a water

consulting company (Emscher Wassertechnik) and a University (Leipzig University, chair of service

management) were making up a consortium to develop professional training courses. The aim of the

project was “Internationalising of Professional Training in the Mining Sector to Support Sustainability

in Resource Management”. Vietnams coal mining sector was chosen as an example and the state

owned holding VINACOMIN acted as a local partner. A thorough assessment phase during the first

year of the project revealed a number of issues that were addressed in training courses designed on a

pilot scale. Four two-day pilot courses were developed: Mine Management, Project Management in

Mining, Water- and Environmental Management and Occupational Safety in Underground Mines.

These courses were documenting best practice in the named fields by giving lively examples of

relevant proceedings and methods.

The Water- and Environmental Management course contained the four topics “Water management and

safety issues”, “Impact of underground mining on the land surface”, “Water treatment” and “Public

concerns and management”. One key aspect of the first topic was the dewatering of underground mine

areas with stagnant water that can endanger the mine workings by sudden water intrusion. The

comparison of the working practice in a Vietnamese mine as observed during the assessment phase

with the common practice in a German mine lead to the presented example. The lifespan of the

dewatering example was covering several months. It started with the utilization of a 3D underground

GIS System to identify the area filled with stagnant water and illustrated the technical aspects of

identifying the expected water volume and the efforts made to safely dewater the area. The mining

authority was permanently kept informed about the monitoring of the progress of the works. This

routine action was documented and explained in the pilot course. Not only for safety reasons it was

noticed that old goaf workings in the Vietnamese mine were not closed and separated from the active

parts of the mine. This practice leads to a higher air ventilation and consumption in the mine as well as

a higher potential for mine water reactions induced by oxidation.

Sharing of professional experiences was viewed as a beneficial way to improve best practice. We had

a very positive feed back from our pilot courses, although they could not cover topics in full detail.

Future effort is needed to implement full scale training, as this project was partly funded by the

German ministry for education and research. Underground coal mining will be ceased in Germany

within a few years. It is in general of gaining importance to secure sustainable resource management

in all countries that supply resources to countries without domestic resources or resources that cannot

be economically mined. Looking ahead it is necessary to make sure our environmental standards will

stay valid for all our goods all along the supply chain.

Key words: Mine water, training, best practice

Proceedings IMWA 2016, Freiberg/Germany | Drebenstedt, Carsten, Paul, Michael (eds.) | Mining Meets Water – Conflicts and Solutions

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Introduction

The approach of our training project was not to deliver text book courses but to create custom made

training courses. The idea was to bring together experts and collect upcoming questions. The

advantage of this method is the involvement of the future trainees in the design of the courses. Many

educational trainers support the assumption that learning is only possible through self-discovery and

self-appropriation (Rodgers 1969). For that purpose a team of around ten German experts visited

repeatedly the Vietnamese hard coal production region Quang Ninh and met with Vietnamese experts.

The project was partly funded by a German government initiative to propagate vocational education

(BEX 2016). A number of open cast mines and underground mines were visited. The Vietnamese

experts were interviewed and a broad spectrum of themes were addressed. Vietnamese experts were in

turn invited to visit German mines (see fig.1).

Hard coal mining in the Quang Ninh region is conducted in open cast mines and underground mines.

About 20 open cast mines and 34 underground mines were producing a mass of 34 million tons in

2011 according to the data presented to the project team. The depth of the open cast mines is

continuously increasing and at some places mining is switching from open cast mining to underground

mining.

Figure 1 Mines visited by the joint project team in Vietnam and Germany.

To our German underground mining expert approaching the Quang Ninh mining region was

reminiscent of Germany‘s Ruhr district in the early 1970s, with shades of grey everywhere, turning to

black in places. The inspection report reads as follows. At the roadsides, locals would prepare meals

over briquettes made from coal dust swept together and moulded in special presses. There was

inadequate binding of the dust from underground, and particularly from the opencast mines, so

residents could make use of the fuel they found on the surface. On arrival we saw several buildings

with recreational rooms, a comparatively large washhouse for staff, a changing room for more senior

staff and a small store. Our group received sets of clothing reserved for what seemed to be rare visitors

– blue dungarees, a jacket, foot rags and half boots but no gloves, goggles or earmuffs. Off we went to


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the portal. On the way to the production site it was remarkable to see that disused roads and galleries

were not dammed off. Instead, a cross made from wooden slats was put up as a No Entry sign. There

was therefore a serious risk of producing fugitive air with dangerous gas concentrations. The condition

of the entire roadway was not state of the art, with hardly any of the support segments connecting up

to the rock. While this is tolerable at prevailing roof pressures, it would be unpardonable when mining

at greater depths with running water in galleries and no pump sumps, making accidents on the

travelling ways a serious possibility. The production site, with a seam thickness of about 2 m and a

cutting drum in operation, lacked sufficient support resistance in the area of face-to-roadway

transition. Except for a wooden prop on the face conveyor gear box, no other support segment was

visible. The cutter pick had sprinkling similar to RAG’s own Eickhoff cutting drums (fig. 2). Miners

would walk across the conveyor and move around in unprotected environments. During the inspection,

no miners who could be identified as managers were in sight. Earlier interviews had revealed the

shortage of qualified personnel in this mining region, which was clearly borne out by appearances. Not

a single member of staff had personal protective gear. Nearby we heard pneumatic hammers being

used in manual coaling, which provides most of the output.

Figure 2 Drum shearer seen in the visited underground mine.

During the discussions with Vietnamese experts the two subjects in the field of mine water that

attracted most interest were dealing with mine water from an operational viewpoint, and eco-friendly

regional water management.

As regards mine drainage, draining dead water (“pockets” as they are known in Vietnam) was of main

interest. This operation is very different from conditions in Germany where dead water is limited to

regions without drainage which have been created in the rock mass by previous mining. These are

visualised with a digital mine plan and provisionally drained by selective boring using highly skilled

personnel underground, who have to follow very specific procedures and are supervised by the Mining

Authority. When draining these regions, water pressures and flows are constantly monitored, with

continuous adjustment of expected and actual readings. Safety equipment (pumps) is kept ready on

site, and mine rescue squads are on standby to minimise the risk of inundation.

Training Courses

Four major topics for training courses were defined during workshops held at VINACOMIN’s

headquarters in Hanoi. During the workshops each topic itself was divided into subtopics according to

the expressed requirements. The course Water- and Environmental Management contained four main


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subjects. Water management and safety issues contained the most prominent issues that had been

discussed.

The mine water management of stagnant waters encountered in the underground when approaching

areas that had been worked in before was extensively discussed with experts from the Auguste

Victoria colliery at Marl/Germany in order to derive a model case for presentation at the pilot course

in Vietnam. The methods used in Germany were debated and documented in detail to make the model

as practical and comprehensible as possible. German mining techniques were illustrated by a variety

of maps, sketches and photos provided by the project partners (fig. 3).

Figure 3 Dewatering scheme to manage stagnant water in a RAG mine.

Many of those on the Vietnamese side had been to the above mentioned colliery during an excursion

organised for the Vietnamese project group. Work underground is not a prestigious job in Vietnam,

and mines find it difficult to recruit suitable trainees. Mines are located in remote areas, and higher

wages cannot compensate for what is available in terms of housing and leisure facilities; it remains an

unattractive option. Flooding is a major risk when working underground, and water pockets may turn

out to be crevasse zones with links to the surface. These are not explored in advance and are not

shown in the mine plan, which consists of paper maps. In geohydraulic calculations, empirical

formulas are inserted for analytical purposes without any numerical simulation. There is no close

monitoring of drainage procedures by the Mining Authority. This subject was addressed in the public

concerns and management part.

The pilot courses were designed to show the advantages of mechanisation in mine operations, and the

German experts have tried to illustrate their own procedures in a comprehensible and practical

manner. The environmental compatibility of water management in mining regions also differs from

the situation in Germany. For example, a first mine water treatment plant had been built under

Germany’s RAME project (Bilek 2011).

At Halong, water-borne coal dust and other substances entering the bay are a major problem. In this

connection, tourism can be a compelling reason for reducing the many environmental burdens

generated by mining. One of the aims of the pilot course was to illustrate the German approach to

mining and the environment, including forecasts of expected negative effects and suitable steps to

avert or abate them. We have tried to show how planning to adapt surface starts years before mining

subsidence can occur. Examples have been given of how forecasting and planning tools interact at

technical level, and of cooperation between mining companies, regulatory agencies and experts at

administrative level.


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Mine water treatment was also discussed in detail during the pilot course. This included a presentation

on general strategies to avoid or minimise the generation of polluted mine water. Details of modern

and efficient mine water treatment plants recently built in central Germany were also presented, with

planning and implementation described by those who had done the job (fig 4). But also technical

simple in-situ-conditioning methods as operated for iron abatement in central Germany and its

implementation in the mine operation processes were discussed. The idea was to convey an experience

that was highly authentic, and to avoid lecturing. Some trainees knew the plants and equipment

involved already from the excursion mentioned. The gathering of data needed to design a treatment

plant was illustrated. In the mining context this means the prediction processes expected in the future.

Figure 4 MIBRAG Mine water treatment plant.

An example for unwanted effects of mining on the ground surface in Germany is shown in fig 5. In

this case the anticipatory regulation of surface waters by hydraulic construction was not appropriate to

avoid water logging. The negative effects had to be cured after the event. In the courses it was shown,

how predictions of future ground water levels were made and how these facts are communicated with

the public and the authorities. The role of certified expert referees in Germany was explained. It was

presented how participation of public is organized in the process of mine planning and the planning of

the compensation of negative effects.

Figure 5 Water logging caused by land subsidence in the German Ruhr coal area.


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Conclusions

With our training courses we were able to point out a number of technical aspects that we believed are

part of best practice when dealing with mine water management. On the other hand we encountered a

number of non-technical reasons for many shortcomings. One reason being the lack of skilled labor.

The reason for that often is that people consider the work in mines as unattractive. We met a large

number of highly qualified and university/college trained managers and executives in mines, at

corporate headquarters and at the Hanoi Mining University who had often studied in Germany or other

countries. While modern technology is on the advance in everyday urban life, it has bypassed the

workers in mining industry.

A number of parallels were found when problems in different mining regions were discussed; our

Vietnamese colleagues found it hard to understand the concept of water management which involves

the long-term raising of water, to be conducted in the Ruhr district in perpetuity. This is in strong

contrast to the Vietnamese principle of leaving most environmental effects unregulated. The country

will hopefully find a middle course here in the future. Germany’s experience in the field can be very

useful, as has been confirmed by many of the trainees who attended courses in Vietnam. From our

point of view, the introduction of German commercial products for education and training could be

hampered by competing services granted free of charge as part of German development aid to

Vietnam.

Acknowledgements

The collaborative project train@mine was co-funded by the German Federal Ministry of Education and

Research, DLR Project Management Agency, exportation of vocational education and training. We would like to

thank all our colleagues in Vietnam and Germany that were engaged in the project.

References

BEX (2016) Federal Ministry of Education and Research, DLR Project Management Agency, exportation of

vocational education and training (http://www.berufsbildungsexport.de)

Bilek F; Brömme K, Stolpe, H (2011) Active Treatment of Fe-, Mn- and Coaldust Contaminated Mine Water as

Part of the RAME-Project in Vietnam, in: 11th IMWA Congress „Mine water – Managing the challenges“,

September 4th-11th 2011, Aachen, Germany, S. 281-286

Rogers CR. (1969) Freedom to Learn: A View of What Education Might Become. (1st ed.) Columbus, Ohio:

Charles Merill.


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Documents

Mine Water Issues addressed in the project train@mine · year of the project revealed a number of issues that were addressed in training courses designed on a pilot scale. Four two-day